Although Ayutthaya is only about 80 km from where we live in Bangkok wife and I want to drive there and spend the night for a more relaxing sightseeing trip, as neither of us have been there before. Can anyone recommend a decent place for around B1000 that also has car parking?

The Woraburi has quite a decent car park. It may be a little over 1,000 Baht though. I think they may have a promotion for around 1,500 inc. breakfast.

there is each next house hotel. Start from 300 bath with car parking

Tony's Place on the island in the centre of town is a good option. it is listed as a guest house but the rooms are actually very well appointed (air-con, hot water, comfy beds etc). There is car parking out the front, with a guard for security. It is situated in 'Soi Farang', which has a nice little range of bars and restaurants, as well as bicycle rental shops should that be the way you would like to get around.

Classic Kameo Hotel&Serviced Apartments, Ayutthaya

Excellent, worth the extra :-)